66 
THE PERIODICAL CICADA. 
in many thousands and occasionally hundreds of thousands together, 
in some cases being intermingled with the ordinary open burrows. At 
New Baltimore, K. Y., 10 miles south of Albany, as early as the last 
week in April the pupa? had brought up, apparently from a considerable 
depth, masses of soft clay-like material and molded it above the ground 
into conical and cylindrical structures for their temporary occupancy. 
In places the ground was almost covered with them, as many as twenty- 
five being counted to the square foot. The cones inclined at a consider- 
able angle from the perpendicular 
and measured from 2 to 3£ inches 
in height, and the chamber within 
was uniform in diameter with the 
hole in the ground. In emerging 
the pupa made a round opening in 
the upper part of the chamber for 
its escape. The accompanying fig- 
ures (fig. 29), published by Dr. Lint- 
ner in the report cited, represent two 
of the chimneys about two thirds of 
their natural size. 
In the Twelfth Report cited a long 
list of localities in New York is given 
where they were found in 1894, to- 
gether with notes on the character 
of the chambers and accompanying 
conditions of the soil, and also on the method of their construction. 
Two of the plates illustrating this report are reproduced in this bulletin 
(see Pis. II and III). They are reproductions of photographs of small 
areas of cone- covered districts. 
Two very elaborate accounts of these structures, by Mr. Benjamin 
Lander and Dr. E. G. Love, were published in 1894-95, the authors 
seeming very near the actual truth in their explanation of the phe- 
nomenon. Mr. Lander describes the occurrence of the cones as noted 
by him as follows : 
On the 4th of May, 1894, while in the woods on the summit of South Mountain, at 
Nyack, N. Y., I came upon a spot that had recently been burnt over. On this area I 
observed vast quantities of the Cicada structures, entirely closed, averaging about 
2\ inches in height, the aggregation ending at the very edge of the burnt section. 
So thickly studded was the ground that often eight or ten would be found in the 
space of a square foot; in one case I counted twenty-three in such a space. Subse- 
quent explorations showed that the Cicada city extended over an area of not less 
than 60 acres. Eight large aggregations were discovered by me on top of the Nyack 
hills and the Palisades, covering many acres, and one near a stone quarry at a lower 
elevation — none of them in a place subject to overflow. Later, when only the ruins 
of the domes remained, I visited two areas where large numbers had been found, one 
in ground thinly covering massive sandstone and another hard by a quarry, where 
the top soil was thin. 
The explanation offered by Mr. Lander is that the dome builders, 
Fig. 29. — Clay buildings of the periodical Cicada 
(after Lintner) 
